Gun barrel locating structure



Nov. 19, 1968 A. PACHMAYR ETAL 3,411,404

GUN BARREL LOCATING STRUCTURE Filed Dec. 29, 1966 3 Sheets-Sheet 5 l NVEN TORS I'QANK .5. PAcH/vm YE EDWARD .B. MIL/.52

United States Patent 3,411,404 GUN BARREL LOCATIN G STRUCTURE Frank A.Pachmayr and Edward B. Miller, Los Angeles, Calif., assignors toPachmayr Gun Works, Inc., Los Angeles, Calif., a corporation ofCalifornia Filed Dec. 29, 1966, Ser. No. 605,825 9 Claims. (Cl. 89-163)ABSTRACT OF THE DISCLOSURE A gun having a hollow slide which recoilsrelative to the receiver and barrel of the gun, with the breech end ofthe barrel being connected to the receiver by a link causing downwardswinging movement of that end of the barrel during recoil, and with theforward end of the barrel being located by a bushing which is secured tothe slide by a pivotal connection, so that the bushing recoils with theslide relative to the barrel and link, and at the same time pivotsrelative to the slide to enable the downward movement of the breech endof the barrel.

This invention relates to improvements in the construction of guns,particularly in guns having an action of the type utilized in certainautomatic pistols, with the improvements being designed for the purposeof increasing the accuracy of such guns. Certain features of theembodiments illustrated in this application have been disclosed andclaimed in US. Patent Number 3,207,037, issued Sept. 21, 1965, on PistolBarrel Mounting Structure, inventors Frank A. Pachmayr et al.

The guns with which the present invention is concerned are of a typehaving a slide which reciprocates rearwardly and then forwardly relativeto the receiver of the gun during recoil, and relative to the barrel.This recoiling motion may be utilized for effecting removal of a firedcartridge case from the gun, and advancement of a next successivecartridge into firing position. During recoiling movement of the slide,the breech end of the barrel may swing slightly downwardly andrearwardly, to a slightly retracted position for facilitating orenabling the recoiling of the slide.

Guns of the above discussed type as conventionally manufactured are veryinaccurate by reason of the ineffectiveness with which the slide,barrel, and receiver are held in alignment with one another, and byreason of the looseness normally encountered in the connections betweenthese various parts, as a result of which there is no reliably andprecisely maintained relationship between the gun barrel and the sightsof the gun. Consequently, even though a marksman may aim the gunperfectly insofar as the sights are concerned, and may be completelyconsistent in such aiming, slight changes in the positioning of thebarrel relative to the sights after different recoiling operations canintroduce errors into the firing of the gun which are completely beyondthe control of the user.

The general object of the present invention is to provide improvementsin the manner in which the various parts of a gun of the discussed typeare interconnected, constructed, and interrelated, for the purpose ofaccurizing the gun and rendering its aiming characteristics more preciseand continually reliable. Certain features of the invention relate to aunique structure for mounting the forward end of the barrel to theslide, in a manner allowing for the discussed slight swinging movementof the barrel relative to the slide during a recoiling motion, but atthe same time so locating the barrel as to completely control theaccurate alignment of its forward portion when in firing or batterycondition. To accomplish this result, we employ a bushing which isdisposed about and locates the forward portion 3,41 1,404 Patented Nov.19, 1968 ICC of the barrel, and is slidable axially along the barrelupon recoiling movement, together with a connection which attaches thebushing to the slide for recoiling movement therewith, and foressentially pivotal movement of the bushing relative to the slide duringrecoil. Preferably, the mentioned connection is of a trunnion type,including two axially aligned pivotal connections at opposite sides ofthe barrel, connecting the bushing to the slide for the desired pivotalmovement.

Additional features of the invention relate to the manner in which thebreech end of the barrel is connected to the receiver for its slightrecoiling movement, preferably by a link structure having a novelinterrelationship with the receiver acting to precisely predetermine theextent of the swinging movement of the barrel as it returns to firingposition.

To further enhance the aiming accuracy of the gun, we in one form of theinvention desirably connect the forward sight of the gun directly to thebushing, rather than to the slide, to thus completely eliminate anychange in relationship between that forward sight and the barrel.

The recoiling movement of the slide may be resisted yieldingly by a coilspring. Another feature of the invention resides in a novel arrangementfor transmitting the forward forces exerted by this spring to the slide,by means of a unique retaining element which may be mounted to the slidefor bodily sliding movement essentially transversely of the barrel andbetween predetermined active and inactive positions. This retainingelement may engage the forward end of a plug which is urged forwardly bythe coil spring.

Still another feature of the invention has to do with the formation ofthe spring and other parts in a manner such that, in the full recoilposition of the slide, the motion of the slide is limited by directmetal to metal contact between successive turns of the spring, which ineffect converts the spring to a rigid essentially integralstop-structure supplementing the effect of other stop-shoulders in thegun.

The above and other features and objects of the invention will be betterunderstood from the following detailed description of the typicalembodiments illustrated in the accompanying drawing, in which:

FIG. 1 is a side view of an automatic pistol constructed in accordancewith the invention;

FIG. 2 is a greatly enlarged side view of the pistol, with some elementspartially broken away;

FIG. 3 shows the gun in recoil position;

FIGS. 4 ,5 and 6 are views taken on lines 4-4, 5-5 and 6-6 respectivelyof FIG. 2;

FIG. 7 is a fragmentary horizontal section taken primarily on line 7-7of FIG. 3;

FIGS. 8 and 9 are vertical sections taken on lines 8-8 and 99respectively of FIG. 2;

FIG. 10 is an enlarged section on line 10-10 of FIG. 8;

FIG. 11 is a perspective view of the barrel mounting link;

FIG. 12 is a fragmentary side view of a variational type of frontbushing structure;

FIGS. 13 and 14 are views taken on lines 13-13 and 14-14 respectively ofFIG. 12, and partially broken away;

FIG. 15 is a fragmentary vertical section taken on line 15-15 of FIG.13; and

FIG. 16 is a plan view of the FIG. 12 bushing.

Referring first to FIG. 1, we have shown at 10 a gun of a well knownconventional type to which the features of the present invention may beapplied, and in connection with which these features will be discussed.This pistol includes a receiver or main body par-t 11, having a handle12 and a trigger 13. A magazine represented at 14 is contained withinthe handle 12, and holds a series of shells which are sequentially fedto firing position and then automatically ejected from the gun uponsuccessive actuations of the trigger. To the upper side of receiver 11,there is movably mounted a slide 15, which is mounted slidably to thereceiver for recoiling movement between the battery or firing positionof FIGS. 1 and 2, and the full recoil position of FIG. 3, and which isthen returned by a spring 16 (FIG. 2) to the FIGS. 1 and 2 position.This rearward and then forward reciprocating movement of the slide isalong the front to rear axis designated 17 in FIG. 2.

Contained within the slide, there is a barrel 18, which is approximatelyaligned with the slide, but whose axis 19 is actually inclined slightlyupwardly and rearwardly in the FIG. 2 battery position. During recoil,the breech end of the barrel 18 swings slightly downwardly to the FIG. 3position, with the movement and positioning of the breech end of thebarrel being controlled by a link assembly designated generally by thenumber 20, and

with the forward or muzzle end of the barrel being' located by a bushing21.

The manner in which slide is mounted and guided for its recoilingmovement is brought out best in FIG. 6, which illustrates that thereceiver has two upper edges 22 forming oppositely directed parallelflanges 23 extending in a front to rear direction, and coacting withinwardly directed parallel flanges 24 formed on the lower edges of slide15, in a relation such that each of the flanges 23 and 24 is receivedwithin a recess or guideway in the other part, to guide the slide forits desired front to rear recoiling movement, while precludingsubstantial movement in any other direction.

The barrel 18 of course forms essentially a tube, having an innersubstantially cylindrical bore or passage 25 centered about axis 19 andopen at its rear end to receive a cartridge, and open at its forward endfor discharge of the projectile. Externally, barrel 18 has a cylindricalsurface 26 extending rearwardly from its forward end 27 to a location28. Beyond this location, the

barrel may enlarge slightly externally, to form a pair of upwardlyprojecting semi-circular ribs 29 receivable within mating recesses 30formed in the interior of slide 15. As will be apparent from FIGS. 2, 5and 6, the slide extends about the upper side of the barrel, and extendsdownwardly at its opposite sides, and has an enlargement 31 extendingdownwardly from the forward end of the slide for coaction with recoilspring 16. An opening 32 in the upper side of the slide allows forejection of the fired cartridge case in the recoil position of FIG. 3.

About the forward cylindrical surface 26 of barrel 18, there is disposedthe previously mentioned bushing 21 (FIG. 2), which is tubular and hasan inner straight cylindrical surface 34 of a diameter correspondingsubstantially to the diameter of outer surface 26 of the barrel, and aclose enough fit on that surface to accurately locate the barrelrelative to the bushing, while still allowing free rearward slidingmovement of the bushing relative to and about the barrel to the positionof FIG. 3. Externally, the bushing may have outer cylindrical surfaces35 and 36 centered about the axis 19 of the bushing and barrel, with anenlarged diameter spherically curved outer surface 37 located betweensurfaces 35 and 36, and centered about a point on axis 19. At itsforward end, the bushing may carry an essentially annular enlargeddiameter flange 38, which may be cut away arcuately at its underside, at39 (FIG. 4), and which carries at its upper side a forward sight 40 foraiming the gun. This forward sight coacts with the usual rear sight 41,which may be carried by the rear portion of slide 15, to define anaiming or sighting line 42 which is parallel to or essentially parallelto axis 19 of the barrel and bushing.

Bushing 21 is connected to lide 15 for relative pivotal movement aboutan axis 43 disposed transversely of the barrel and bushing and theirlongitudinal axis 19 (FIGS. 2 and 5). For this purpose, we provide twopivot or trunnion elements 44 (FIG. 5), each of which may take the formof a screw having threads 45 centered about axis 43 and connected intothreads 46 also centered about that axis and formed in the slide. Eachof these screws may have an enlarged head 47 which is tightenableagainst the vertical outer surface 48 of the slide, and containing ascrewdriver slot. Inwardly beyond its threads 45, each screw may have anexternally cylindrical reduced diameter portion 49, centered about axis43, and received within a correspondingly dimensioned cylindricalopening 50 formed in one side of bushing 21, to mount the bushing forthe desired pivotal movement about axis 43. The fit between surfaces 49and 50 should be close, to prevent any relative motion between thebushing and elements 44, so that the bushing can only move pivotally. Aswill be apparent from FIGS. 2 and 5, the outer spherical surface 37 ofthe bushing is centered about a point 51 located at the intersection ofaxes 19 and 43, and is of a diameter corresponding to the diameter of anengaged inner cylinsurface 52 formed in the slide, so that theinterengagement of surfaces 37 and 52 coacts with trunnion elements 45in preventing upward, downward or lateral movement of the bushingrelative to the slide.

At its breech end, barrel 18 has a downwardly projecting connectorportion 53, which is integral with the rest of the barrel and may formtwo laterally spaced depending lugs 54 (see FIG. 6), each having theside view configuration illustrated in FIG. 2. Lugs 54 are pivotallyconnected by a pin 55 to a link 56, which forms with the other relatedparts the link assembly heretofore referred to generally by the numeral20, for controlling the movement of the breech portion of the barrel.Link 56 is in turn pivotally connected to receiver 11 by a pin 57 (FIGS.2 and 6), which extends through and is located by two cylindricalpassages 58 formed in opposite sides of the receiver. Pin 57 has anenlarged head 59 at one of its ends, and adjacent the head extendsthrough an opening within the usual slide stop 60, which coacts with theslide to hold it in open or recoil position under certain operatingconditions. As will be understood, slide stop 60 is in most guns of thepresent type integral with pin 57, but in accordance with the teachingsof Patent Number 3,207,037, we prefer to form it separately from the pinas shown. At the second side of the receiver, the pin 57 may be held ininstalled position by means of a retaining snap ring 61, which may beresilient and extend more than half way about pin 57, a d. be receivedwithin an annular groove 62 to retain the pinagainst removal.

,Pins 55 and 57 are disposed about axes which extend transversely of therecoiling axis 17 of the slide, and transversely of axis 19 of thebarrel and bushing, though not actually intersecting these axes. Link 56has an upper portion 63 which extends upwardly between, and is a closefit between, the two depending lugs 54 of the barrel, with pin 55extending through mating apertures in lugs 54 and end portion 63 of thelink to interconnect these parts for the desired relative pivotalmovement between the positions of FIGS. 2 and 3. Beneath its portion 63,link 56 may have a widened portion 64. As best seen in FIG. 6, thisportion 64 of the link, and the two lugs 54 on the barrel, have parallelplanar surfaces at their opposite sides which are spaced incorrespondence with the spacing of inner vertical planar surfaces 66defining the opposite sides of a recess in the receiver within which thelink is contained, so that the opposite sides of the link and of lugs 54simultaneously engage both of the surfaces 66, to effectively confinelink 56 and lugs 54 against any lateral movement, longitudinally of pins55 and 57. Surfaces 66 in the receiver and the engaged surfaces of thelink and barrel lugs are of course disposed transversely of pins 55 and57, and therefore lie in planes which are essentially parallel to axes17 and 19.

At its underside, and forwardly of the axis of pin 57, link 56 has aplanar undersurface 67, which in the battery position of FIG. 2 extendsdirectly horizontally and abuts downwardly against a horizontal bottomwall surface 68 formed in the receiver. Thus, this interengagement ofsurfaces 67 and 68 acts to positively limit the upward and forwardmovement of the barrel in the FIG. 2 position. In the FIG. 3 position,two rearwardly facing vertical planar surfaces 69 formed on the backsides of lugs 54 engage a vertical planar surface 70 formed in thereceiver and disposed perpendicular to axis 17, to prevent any furtherrearward and downward movement of the barrel. It is also noted that, inthe FIG. 2 position of the barrel, pin 55 is desirably locatedapproximately directly above pin 57 (preferably slightly forwardly of aposition of exact vertical alignment of the pins). Because the pins arein this approximate vertical alignment, any slight forward or rearwardshift which may occur for any reason in the firing position of thebarrel can not alter substantially the vertical position of the breechend of the barrel, or the position of barrel axis 19.

The forward end of helical recoil spring v16 is received within andbears forwardly against a plug 71, which contains a cylindrical passage72, Within which the spring is a fairly close fit. The forward end ofthe plug forms a transverse wall 73 against which the spring bears, and:which has a reduced diameter externally cylindrical portion 74 and aforward annular transverse surface 75. Except at the location of thisforward portion 74, the plug may have an increased diameter externalsurface 76 which is slidably received and located within a cylindricalpassage 77 formed in the downwardly projecting forward portion 31 of theslide. The plug is retained against forward movement relative to theslide, to transmit forward forces of the spring to the slide, by meansof a retaining element 78, which is slidably received within a guideway79 formed in portion 31 of the slide, and extending vertically ortransversely of axis 17. As will be apparent from FIGS. 2 and 8, element78 may take the form essentially of a flat plate, which bridges acrossthe passage 77 in the lower portion of the slide, with the guideway 79in that portion of the slide forming an opening extending across thebottom of the slide at 80, and forming two parrallel internal guidewaygrooves 81 extending upwardly within the opposite side portions 82 ofthe slide portion '31. The peripheral shape of retaining element 78 isbrought out best in Fig. 8, which illustrates the part as having a lowerexternally semicircular portion 178 which is received within opening 80and has its outer semi-circular surface 278 flush with the outer surface131 of slide portion 31. Above portion 178, element 78 has two parallelvertical edges 278 which are slidably received and guided within grooves81. Element 78 also has an essentially central opening 83 dimensioned incorrespondence with forward reduced diameter portion 74 of plug 71, toreceive that portion of the plug in interfitting relation in a mannerlocking element 78 against downward removal from the slide.

The rear end of'the compression spring 16 is received about a springguide 84, having a flange 85 at its rear end against which the springexerts rearward force. This flange 85 in turn bears against a forwardlyfacing shoulder 86 formed in and by the receiver, with a portion 87 ofthe guide projecting rearwardly beyond that shoulder. This portion 87 ofthe guide is in conventional guns of this general type annular, but inaccordance with the present invention is specifically formed to avoidinterference with the forwardmost portion of link 56, and for thispurpose portion 87 of the, guide 84 is milled to form a verticallyextending slot or cutaway as shown at 88 in FIGS. 7 and 9. The forwardportion of link 56 is reduced somewhat in width at 89 (FIGS 2, 7 and11), so that this slightly reduced width portion of the link may rnoveupwardly and downwardly within the slot or cutaway 6 area 88 in guide 84as the link pivots between the positions of FIGS. 2 and 3.

The rearward recoiling movement of slide 15 is in most guns of thepresent type limited by engagement of the thickened essentially annularportion 90 (FIG. 3) of the slide with the flange of spring guide 84. Tosupplement this motion limiting action, we so dimension the variousparts and partcularly spring 16 that, in the fully recoiled position ofFIG. 3, the successive turns of the spring are all in direct essentiallyannular engagement with one another, so that there is direct metal tometal contact (continuously throughout 360 circular degrees) between allof the various successive turns of the spring, and between the end turnsand the parts engaged thereby, to thus in effect form through the springa rigid metal connection between surface 73 at the forward end. of plug71 and the flange 85 of spring guide 84, to in this way coact with thepreviously mentioned engagement between portion of the guide and flange85 in positively limiting the recoiling motion.

To now describe a cycle of operation of the pistol shown in FIGS. 1 to11, assume that the gun is in the battery condition of FIG 2, and that aloaded magazine has been inserted into the handle of the gun, and thatone round has been properly positioned in the breech end of the barrel.With the gun in this condition, the user may aim the gun by means ofsights 40 and 41, and then pull the trigger so that hammer 91 causesfiring pin 192 to fire the shell which is in the barrel. The gases ofcombustion produced in the barrel act through the cartridge case toforce slide 15 rearwardly relative to the receiver and barrel to theFIG. 3 recoiled position. During the initial portion of this slidemovement, the recoil forces also cause the breech end of the barrel toswing rearwardly and downwardly to its FIG. 3 position, about axis 43,with this motion of the barrel being limited by engagement of lugs 54with receiver shoulder 70. The rearward motion of the slide causesejection of the fired cartridge case, and enables a next successiveround to move into firing position in the barrel, following which spring16 returns the slide forwardly to its FIG. 2 position, with theforwardly facing vertical shoulder surface 92 of the slide firstshifting the cartridge forwardly into the barrel, and then engaging thebarrel itself during the final portion of the slide movement to forcethe barrel forwardly and upwardly from its FIG. 3 position back to itsFIG. 2 position, in preparation for the next successive firingoperation.

The trunnion mounting of the muzzle-end of the barrel very effectivelylocates that portion of the barrel in precisely predetermined positionrelative to the slide, when the parts are in the battery condition ofFIG. 2, and in spite of the limited pivotal movement permitted betweenthese various parts during recoil. Also, the link 56 and its relatedparts effectively locate the breech end of the slide, preventing anylateral movement thereof, and precisely predetermining the height of thebreech end throughout its complete cycle and in its final position. Thisfinal battery position of FIG. 2 is rendered very accurate by limitingthe returning movement of the barrel by engagement of the previouslydiscussed shoulder or surface 67 on link 56 with the upwardly facingsurface 68 in the receiver. In this connection, it is noted that thereis preferably no motion halting interengagement between the link andlugs 54 at the location designated 92' in FIG. 2, or between any othersurfaces except at shoulder 67, so that the engagement of this shoulderon link 56 with surface 68 may desirably function alone to determine theforwardmost position of the barrel.

When it is desired to dismantle the gun, or for other reasons haveaccess to spring 16, a person may merely press the reduced diameterforward portion 95 of plug 71 rearwardly out of the opening 83 ofretaining element 78, and far enough to enable the retaining element tobe slid downwardly, transversely of the axis 96 of the spring, and

out of the guideway 79, so that the plug and spring may be withdrawnforwardly from the slide. Bushing 21 may be removed by unscrewing theretaining trunnion elements 44, and the other parts of the gun may bedismantled in conventional manner.

FIGS. 12 through 16 show a variational type of bushing 97 which may besubstituted for the bushing 21 of FIGS. 1 to 11, and which functions asdoes bushing 21 to accurately locate the forward end of a gun barrel 18aand mount that barrel for only predetermined limited pivotal movementrelative to a gun slide 15a about a transverse axis 43a corresponding toaxis 43 of FIG. 4. Except with respect to the structure at bushing 97,and the other features discussed hereinbelow, the gun of FIGS. 12through 16 may be considered as essentially identical with that of thefirst form of the invention.

' Bushing 97 of FIGS. 12 through 16 is desirably stamped from a singlepiece of sheet material, preferably high quality sheet steel heattreated after stamping to spring temper. This sheet material is stampedto provide a vertically extending front wall portion 98 of the bushing,which extends vertically in front of and in spaced relation to the planeof vertical end surface 99 of slide 15a. At the center of this verticalwall 98, the sheet material is shaped to provide a rearwardly projectingtubular portion 100 of the bushing, which portion has an innercylindrical surface 101 corresponding substantially in diameter to theouter cylindrical surface of barrel 18a, to guide the bushing for axialsliding movement along the barrel. This tubular portion 100 of thebushing extends rearwardly into the interior of the slide, as seenclearly in FIG. 15, and is spaced radially from the slide at 102 toenable the desired limited pivotal movement of the bushing with thebarrel.

At its opposite sides, the sheet material of bushing 97 forms tworearwardly projecting parallel mounting arms 103, which may be identicaland lie in parallel vertical planes, and which abut laterally againstthe vertical parallel opposite side surfaces 104 formed on slide 15a.These side surfaces 104, and the arms 103, lie in vertical planes whichare parallel to the vertical central plane 105 of the gun extendingthrough axis 106 of the barrel. As will be understood, the abuttingengagement of the inner vertical planar surfaces 106 of arms 103 withslide surfaces 104 effectively locates the bushing 97 against lateralmovement relative to the slide.

Arms 103 contain two aligned openings 107 (FIG. 14) Within which thereare received two pivot screws 108 having externally threaded shanksscrewed into internally threaded passages 109 formed in the oppositeside walls 110 of the slide. Screws 108, passages 109, and openings 107are all centered about transverse axis 43a, so that the screws guidearms 103 and the rest of bushing 97 for the desired pivotal movementabout that axis. For this purpose, the head 111 of each of the screws108 has an outer cylindrical surface 112 centered about axis 43a, whichsurface engages in closely fitting bearing relation a correspondinglycylindrical surface 112 of the opening 107 in the associated arm 103,with surface 112 also being centered axis 43a. The forward sight 40 ofthe gun shown in FIGS. 12 to 15 is typically illustrated as mounted tothe forward end of the slide, in essentially conventional manner.

In using the gun of FIGS. 12 to 16, the operation is substantiallyidentical with that previously discussed in connection with FIGS. 1through 11, except for the difference in structure of the bushing 97. Asin the first form of the invention, this bushing pivots aroundtransverse axis 43a, as the bushing and slide recoil rearwardly relativeto barrel 18a, with this slight pivotal movement of the bushing beingsufiicient to enable the desired slight rearward and downward swingingmovement of the breech end of the barrel during recoil. The spacing ofbushing 97 from the forward end surface 99 of the slide and from theinner surfaces of the slide at 102 (FIG. 15) is sufficient to avoid anyinterference with the desired pivotal movement of the bushing. As in thefirst form of the invention, the barrel is very effectively located bythe bushing, and very accurately and precisely maintained in a desiredset position relative to the barrel in the battery position of theslide, to avoid any loss of aiming characteristics of the gun such asoccurs in conventional firearms of this same general type in which theforward end of the barrel is only loosely located.

During assembly of the arrangement of FIGS. 12 to 16, the bushing 97 maybe placed in its illustrated position about the slide prior to theattachment of screws 108 to the slide, and the screws may then be veryeasily inserted through openings 107 in arms 103 and screwed into theslide. alternatively, the parts may be assembled in a reverse manner inview of the resilence given to arms 103 by the previously mentioned heattreating of the bushing to spring temper. That is, screws 108 may firstbe connected to the slide, and the bushing then by applied by spreadingits arms 103 sufficiently apart to move them past the screws untilopenings 107 align with the screws, so that the arms may then moveinwardly by their own resilience against the opposite sides of the slideand into interfitting pivotal engagement with the screws.

We claim:

1. A gun including a receiver, a slide mounted for recoiling movementrelative to said receiver, a barrel within said slide mounted for slightupward and downward swinging movement of the breech end of the barrelrelative to said receiver during said recoiling movement of the slide, abushing disposed about and locating said barrel and slidable therealongaxially of the barrel upon said recoiling movement of the slide, and anaiming sight carried by said bushing.

2. A gun including a receiver, a slide mounted for recoiling movementrelative to said receiver, a barrel within said slide mounted for slightupward and downward swinging movement of the breech end of the barrelrelative to said receiver during said recoiling movement of the slide, abushing disposed about and locating said barrel and slidable therealongaxially of the barrel upon said recoiling movement of the slide, and aconnection between said slide and bushing attaching the bushing to theslide for recoiling movement therewith and for essentially pivotalmovement of the bushing relative to the slide upon said slight upwardand downward movement of the breech end of the barrel, said connectionincluding means forming a spherically curved radially outer surface onsaid bushing engageable arcuately with an essentially cylindrical innersurface in said slide.

3. A gun including a receiver, a slide mounted for recoiling movementrelative to said receiver, a barrel within said slide mounted for slightupward and downward swinging movement of the breech end of the barrelrelative to said receiver during said recoiling movement of the slide, abushing disposed about and locating said barrel and slidable therealongaxially of the barrel upon said recoiling movement of the slide, and aconnection between said slide and bushing attaching the bushing to theslide for recoiling movement therewith and for essentially pivotalmovement of the bushing relative to the slide upon said slight upwardand downward movement of the breech end of the barrel, said connectionincluding two axially aligned horizontally extending screws connectedthreadedly into said slide at opposite sides of said barrel and bushingand having pivot pin ends projecting horizontally into mating recessesin said bushing to mount the bushing for pivotal movement about ahorizontal axis relative to said slide, said connection including also aspherically curved radially outer surface on said bushing engageablearcuately with a cylindrically curved inner surface of said slide.

4. A gun including a receiver, a slide mounted for recoiling movementrelative to said receiver, a barrel within said slide mounted for slightupward and downward swinging movement of the breech end of the barrelrelative to said receiver during said recoiling movement of the slide, abushing disposed about and locating said barrel and slidable therealongaxially of the barrel upon said recoiling movement of the slide, aconnection between said slide and bushing attaching the bushing to theslide for recoiling movement therewith and for essentially pivotalmovement of the bushing relative to the slide upon said slight upwardand downward movement of the breech end of the barrel, a rear sight, anda forward sight carried by and projecting upwardly from said bushing andpivotally movable therewith.

5. A gun including a receiver, a slide mounted for recoiling movementrelative to said receiver, a barrel within said slide mounted for slightupward and downward swinging movement of the breech end of the barrelrelative to said receiver during said recoiling movement of the slide, abushing disposed about and locating said barrel and slidable therealongaxially of the barrel upon said recoiling movement of the slide, and aconnection between said slide and bushing attaching the bushing to theslide for recoiling movement therewith and for essentially pivotalmovement of the bushing relative to the slide upon said slight upwardand downward movement of the breech end of the barrel, said bushinghaving a first portion extending essentially vertically in front of theslide and having a rearwardly projecting tubular portion about andslidably engaging the barrel, said connection including two armsprojecting rearwardly from opposite sides of said first portion adjacentopposite outer side surfaces of the slide, and two pivot pins screwedinto said slide at opposite sides of the barrel and received in openingsin said arms to mount the bushing for said pivotal movement.

6. A gun including a receiver, a barrel, a hollow slide extending acrossthe top of said barrel and downwardly at its opposite sides, guidewaymeans mounting said slide to the receiver for front to rear recoilingmovement relative to said receiver and relative to said barrel, linkmeans near the breech end of said barrel connecting said breech endmovably to said receiver in a relation causing slight downward andrearward swinging movement of the breech end relative to the receiverduring and as a result of said recoiling movement of the slide, abushing carried by and within said slide and disposed about and locatingsaid barrel and slidable therealong axially of the barrel upon saidrecoiling movement of the slide, said bushing having portions slidablyengaging both the upper side and underside of said barrel and defining apassage through the bushing within which the barrel is closely butslidably confined, and a pivotal connection between said slide and saidbushing attaching the bushing to the slide for recoiling movementtherewith relative to said receiver and said barrel and said link meansand for pivotal movement of the bushing relative to the slide about anaxis disposed transversely of the barrel upon said slight downwardmovement of the breech end of the barrel.

7. A gun including a receiver, a barrel, a hollow slide extending acrossthe top of said barrel and downwardly at its opposite sides, guidewaymeans mounting said slide to the receiver for front to rear recoilingmovement relative to said receiver and relative to said barrel, linkmeans near the breech end of said barrel connecting said breech endmovably to said receiver in a relation causing slight downward andrearward swinging movement of the breech end relative to the receiverduring and as a result of said recoiling movement of the slide, abushing carried by and within said slide and disposed about and locatingsaid barrel and slidable therealong axially of the barrel upon saidrecoiling movement of the slide, and a pivotal connection between saidslide and said bushing attaching the bushing to the slide for recoilingmovement therewith relative to said receiver and said barrel and saidlink means and for pivotal movement of the bushing relative to the slideabout an axis disposed transversely of the barrel upon said slightdownward movement of the breech end of the barrel, said connectionincluding two axially aligned pivotal connections at opposite sides ofsaid barrel connecting said bushing to said slide for pivotal movementabout only a predetermined horizontal axis disposed transversely of thebushing and barrel.

8. A gun including a receiver, a barrel, a hollow slide extending acrossthe top of said barrel and downwardly at its opposite sides, guidewaymeans mounting said slide to the receiver for front to rear recoilingmovement relative to said receiver and relative to said barrel, linkmeans near the breech end of said barrel connecting said breech endmovably to said receiver in a relation causing slight downward andrearward swinging movement of the breech end relative to the receiverduring and as a result of said recoiling movement of the slide, abushing carried by and within said slide and disposed about and locatingsaid barrel and slideable therealong axially of the barrel upon saidrecoiling movement of the slide, and a pivotal connection between saidslide and said bushing attaching the bushing to the slide for recoilingmovement therewith relative to said receiver and said barrel and saidlink means and for pivotal movement of the bushing relative to the slideabout an axis disposed transversely of the barrel upon said slightdownward movement of the breech end of the barrel, said connectionincluding two axially aligned horizontally extending screws connectedthreadedly into the slide at opposite sides of said barrel and bushingand having pivot pin ends projecting horizontally into mating recessesin said bushing to mount the bushing for pivotal movement about ahorizontal axis relative to said slide.

9. A gun including a receiver, a barrel, a hollow slide extending acrossthe top of said barrel and downwardly at its opposite sides, guidewaymeans mounting said slide to the receiver for front to rear recoilingmovement relative to said receiver and relative to said barrel, linkmeans near the breech end of said barrel connecting said breech endmovably to said receiver in a relation causing slight downward andrearward swinging movement of the breech end relative to the receiverduring and as a result of said recoiling movement of the slide, abushing carried by and within said slide and disposed about and locatingsaid barrel and slidable therealong axially of the barrel upon saidrecoiling movement of the slide, and a pivotal connection between saidslide and said bushing attaching the bushing to the slide for recoilingmovement therewith relative to said receiver and said barrel and saidlink means and for pivotal movement of the bushing relative to the slideabout an axis disposed transversely of the barrel upon said slightdownward movement of the breech end of the barrel, said connectionincluding two arms received at opposite sides of said slide, and pivotpins connecting said arms pivotally to the slide.

References Cited UNITED STATES PATENTS 984,519 2/1911 Browning 89-163 X2,489,816 11/1949 Reilly 89-163 2,865,255 12/1958 Marsh 89163 FOREIGNPATENTS 347,573 1/ 1922 Germany.

BENJAMIN A. BORCHELT, Primary Examiner.

S. C. BENTLEY, Assistant Examiner.

